The Add-ons strategy

The main European energy challenge concerns the efficient renovation of the existing buildings stock, which counts for two third of the overall European energy consumptions; yet up until today, only 1,2% of existing buildings gets renovated every year. The actual investment gap in the deep renovation sector is due to the fact that consistent investments are required up-front and they are generally characterized by an excessively high degree of risk and long payback times. The ambition of this book is to validate an integrated design methodology based upon the creation of additional volume on existing buildings - Add-Ons - intended as roof-top or aside extensions, enclosures, parasites or façade transformations. Add-Ons are intended as the core and main instrument of an innovative strategy, proven able to overcome the actual barriers, increase the feasibility of energy renovation in the residential field and ultimately foster the building renovation market. The empowering synergy between old and new at the base of the Add-ons strategy will be illustrated through design experiments carried in a series of existing buildings in different European contexts.